Among mobile terminal apparatuses such as mobile telephones and personal digital assistants (PDAs), those configured to include a multi-task operating system (OS) are increasing. Among mobile terminal apparatuses equipped with a multi-task OS is an apparatus that has improved functions as well as improved expressional capability and operability of the user interface, and to which rich client software can be added. The mobile terminal apparatus also has various functions other than making and receiving calls, and provides the various functions to the user by executing applications (hereinafter, respectively referred to as “app”) such as, for example, an e-mail app; a web browser; a news app; a viewing app for blogs, etc.; a map app; a traffic information app; and a game app.
The mobile terminal apparatus providing the various functions as described above consumes more electrical power as the number of functions provided increases. For example, a smartphone is an example of a mobile terminal apparatus equipped with a multi-task OS, and also consumes a large amount of electrical power. The functions provided by a smartphone include functions that cause the hardware thereof to operate and the software thereof to be executed consequent to regularly executed processes such as the reception of e-mail and updating of a resource description framework site summary (RSS) even when the user does not operate the smartphone. These functions cause the power consumption of the mobile terminal apparatus to be further increased.
For example, a technique is disclosed as a technique of reducing the increased power consumption. According to the technique, information such as the amount of remaining battery power is mutually declared between a wireless terminal apparatus and a server; the transmission speed, the transmission scheme, and the power source control scheme are set according to the content of the declaration; and thereby, the reduction of the amount of remaining battery power is minimized (see, e.g., Japanese Laid-Open Patent Publication No. H9-205396).
A technique is disclosed as another technique of reducing the power consumption. According to the technique, the arrival time of a packet is estimated; an active state where the electrical power is unlimitedly used is switched to a low electrical power state or the low electrical power state is switched to the active state, based on the estimated arrival time (see, e.g., Japanese Laid-Open Patent Publication No. 2002-185475).
A technique is disclosed as yet another technique of reducing the power consumption. According to the technique, in a wireless communication system, the transmission cycle of a beacon signal that is reported by a base station is set based on a setting request issued by a terminal station (see, e.g., Japanese Laid-Open Patent Publication No. 2005-130436 (Paragraphs and)). According to the technique disclosed in Japanese Laid-Open Patent Publication No. 2005-130436, the terminal station can turn off the power supply to the communication circuit until the timing at which the beacon signal is received by causing the interval for checking an e-mail app executed in the terminal station to be same as the transmission cycle of the beacon of the base station and thereby, the power consumption of the terminal station can be reduced.
A technique is disclosed as a technique of reducing the amount of information in regularly executed processes. According to the technique, the polling time of a packet from a parent station is calculated by a child station based on a database (see, e.g., Japanese Laid-Open Patent Publication No. 2005-33444).
However, among the conventional techniques, according to the technique disclosed in Japanese Laid-Open Patent Publication No. 2002-185475, the amount of data transmitted and received by the mobile terminal apparatus is estimated based on the result of observation and therefore, a problem arises in that the power consumption is increased when a large amount of data is generated. According to the techniques disclosed in Japanese Laid-Open Patent Publication Nos. H9-205396, 2002-185475, and 2005-33444, the apps providing the various functions do not necessarily operate within the extent that is estimated by the mobile terminal apparatus and each of the apps operate independently of the other apps and therefore, a problem arises in that power consumption increases.
According to the technique disclosed in Japanese Laid-Open Patent Publication No. 2005-130436, denoting the transmission process executed by the base station as “app 1” and the check process of the e-mail app executed by the terminal station as “app 2”, the technique disclosed in Japanese Laid-Open Patent Publication No. 2005-130436 is applicable to a mobile terminal apparatus and the app 1 can be run associated with the operation of the app 2. However, a problem arises in that the operation restrictions of the apps may be violated by changing the time at which each of the apps runs.